[Low-temperature preparation of TiO2/PS/Fe3O4, and its photocatalytic activity and magnetic recovery]

Huan Jing Ke Xue. 2012 Aug;33(8):2752-8.
[Article in Chinese]

Abstract

This study reports the fabrication of magnetically responsive titania catalyst, which consisted of a magnetic core surrounded by a titania shell. The magnetic core (oleic acid-modified Fe3O4 nanoparticles) was modified with polystyrene as inert isolating layer. The magnetic photocatalyst was prepared at low temperature (90 degrees C) and a neutral pH (about 7). The phase composition, morphology, surface properties and magnetic properties of the composite particles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), fourier infrared photometer (FT-IR) and vibrating sample magnetometer (VSM). The photocatalytic activity of the samples were determined by degradation of phenol and their recovery characteristics were determined by a self-regulating magnetic recycling equipment. The results illustrated that the mean diameter of anatase titanium dioxide synthesized at low temperature was 2-5 nm, the catalyst TiO2/PS/Fe3O4 [the molar ratio of the magnetic photocatalyst was n(TiO2): n(St): n(Fe3O4) = 60:2.5:1] had the structural integrity of shell/shell/core, and titanium dioxide was loaded firmly on the PS/FeO4 surface. The photocatalytic degradation of phenol followed first-order reaction kinetics and the reaction rate constant K of the TiO2/PS/Fe3O4 [n(TiO2): n(St): n (Fe3O4) = 60:2.5:1] was 0.0258, which was close to that of pure TiO2 (K = 0.0262). After 5 times recycling, the K value reduced only by 0.0034. The catalyst had a strong magnetic induction, and the average recovery rate reached 92%. The magnetic TiO2 photocatalyst prepared by this low-temperature hydrolysis method has a good application prospect.

Publication types

  • English Abstract
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Cold Temperature
  • Computer Simulation
  • Ferrosoferric Oxide / chemistry*
  • Light
  • Magnets
  • Metal Nanoparticles / chemistry*
  • Phenol / isolation & purification
  • Photochemical Processes
  • Polystyrenes / chemistry*
  • Titanium / chemistry*
  • Waste Disposal, Fluid / methods*

Substances

  • Polystyrenes
  • titanium dioxide
  • Phenol
  • Titanium
  • Ferrosoferric Oxide